Synthesis of precipitated calcium carbonate (PCC) nano-particles using turbo-mixing reactive precipitation

Abstract

Calcium carbonate (CaCO3) is a crystalline compound appear abundantly in nature substance mostly in sedimentary rocks which comprise more than 4% of the earth’s crust throughout the world. Calcium carbonate is one of the most extensively studied inorganic compounds because of its importance in the various fields and industrial processes due to its large range of applications. In recent decades, conventional productions of the precipitated calcium carbonate (PCC) only manage to produce particle size not less than 200 nm. In this thesis, an innovative and novel technology method of processing called Turbo-Mixing Reactive Precipitation (TMRP) design proposed as an alternative to this current processing or conventional productions of fine precipitated calcium carbonate (nano-PCC) in turbo-mixing conditions. In the TMRP process, nano-PCC is fabricated using gas-liquid-solid systems (precipitation) of the calcium hydroxide slurry (Ca(OH)2) or better known as “milk of lime” in a stirred tank batch reactor system. Carbon dioxide and nitrogen gas is introduced into the tank through bubbled into the “milk of lime” in the reactor tank. The key research of this study explored new methodologies and optimization the influence parameters in the production of nano-PCC using TMRP technique. The experimental result indicated that the most reactive of quicklime can be obtained by calcined at 1100 °C with 60 minutes of soaking time for sample sized range between -30+20 mm. An average particle size approximately 26.79 nm of CaCO3 nanoparticles was successfully produced by the 15 ℓ/min flowing rate of CO2 gas and O2-free N2 gas, 0.60 M concentrations of Ca(OH)2 slurry and 900 rpm stirring rotation speed at low precipitation temperature (10 ±5 ºC).